tbuckley/cabot-search huggingface dataset:
Abstract P1093: Safety And Feasibility Of Tissue-engineered Biological Ventricular Assist Devices For Ischemic Cardiomyopathy
Authors: Ming Wu, Alain Van Mil, Piet Claus, Michiel Algoet, Andrei Hrynevich, Johannes Braig, Gerardo Cedillo-Servin, Hilde Gillijns, Patricia Holemans, Inge Dokter, Tomasz Jüngst, Miguel Castilho, Jos Malda, Jürgen Gröll, Manuel Mezo, Joost P Sluijter, Wouter Oosterlinck, Felipe Prosper, Stefan P Janssens
Journal: Circulation Research (2023)

Introduction: Advances in material science and cell technology offer new possibilities in myocardial repair. We test the safety and feasibility of implanting epicardial cellularized patches in a porcine ischemic cardiomyopathy model, representative of human disease. Methods: In pigs (n=4) , 90 min occlusion of the circumflex artery induced myocardial infarction (MI) (infarct size at 4w MRI: 16±7% of LV mass with reduced EF 49±12%). To cover the scar, hexagonal multi-layered 4x4cm scaffolds were printed using high-resolution 3D melt electrowriting, and populated with human iPSC-derived cells (90% cardiomyocytes/10% fibroblasts, totaling 90 million cells), loaded in fibrin hydrogel. Four w post-MI and after 2 w immunosuppression, we sutured patches over the infarcted epicardium and monitored arrhythmias with implantable loop recorders for 1 w. Hearts were explanted after a second MRI for histopathology. Results: Pre-implantation cell loss from spontaneously contracting patches was 0.34±0.15% of all iPSC-derived cells. Immunosuppression was well tolerated (normal LFTs and eGFR) and effective and no significant arrhythmias were recorded after patch implantation. MRI showed correct anatomical patch position ( Fig. 1 ). Visual analysis confirmed homogeneous patch attachment and histology evidenced excellent biocompatibility, and marked engraftment of the construct with host vasculature ( Fig. 1 ). Conclusions: We provide proof-of-concept for safety and feasibility of human iPSC-derived cellular constructs of clinically relevant size in porcine ischemic cardiomyopathy. Follow-up placebo-controlled studies are ongoing to evaluate therapeutic efficacy.
Abstract P1113: Patient-derived Cardiac Assembloids Enable Therapeutic Verification Of Regenerative Reagent Bio
Authors: Yong-Sook Kim, Meeyoung Cho, Dong Im Cho, Sooji Yoo, Youngkeun Ahn
Journal: Circulation Research (2023)

Background: Preclinical study is a prerequisite for drug developments, and yet animal models are poor predictors in humans. We previously reported GSK3β inhibitor BIO (6-Bromoindirubin-3’-oxime) induced cardiac regeneration in zebrafish and rat models. Methods and Results: For further development of BIO in the models with human features, we generated human pluripotent stem cells (h-iPSCs) to get the cells which are components of heart. H-iPSCs were derived from blood mononuclear cells, or generated from fibroblasts isolated from the heart tissues of recipients after transplantation or from heart samples during autopsy. After confirming the cell markers, h-iPSCs were differentiated into cardiomyocytes (CM), cardiac myofibroblasts (MF), and macrophages (Mac). Decellularized extracellular matrix (dcECM) were extracted from hearts, and we developed spheroids with various combinations. Since CM hardly proliferate and excessive MF is accumulated in damaged heart, cardiac regeneration is challenged by reversal them. Firstly, the effective dosage of BIO was 0.5uM on human cells, while was 5uM on cardiac cells of mice and rats. On BIO treatment with 0.5μM for 3 days, the numbers of total CM and EdU-or Ki67-positive CM were higher in the BIO-treated CM spheroids. Conversely, viability, migration and collagen gel contraction activities of MF were substantially inhibited by BIO treatment. Conclusions: Because tremendous trials for regeneration have failed in clinical applications, it should be validated in realistic study designs with human cells. Here, we successfully reproduced the effects of BIO on human cardiac cells, and suggest the reciprocal regulation of CM and MF by BIO could be attractive therapeutic to heart diseases. More targeted approaches using human cardiac cells and dcECM might allow specific targeting of cardiovascular disease thus optimize regenerative therapy.
Abstract P3166: Circulating Extracellular Vesicles In Human Cardiorenal Syndrome Promote Renal Injury In Kidney On A Chip System
Authors: Emeli Chatterjee, Rodosthenis Rodosthenous, Ville Kujala, Katia karalis, Lehmann Helge, Michail Spanos, Getulio Oliveira, Tyne Miller, Mingijan Shi, Priyanka Gokulnath, Guoping Li, Ionita Ghiran, Joann Lindenfeld, Jonathan Mosley, Emily Lau, Jennifer E Ho, Quanhu Sheng, Ravi V Shah, Saumya Das
Journal: Circulation Research (2023)

Objective: Cardiorenal syndrome (CRS)—renal injury during heart failure (HF)—is linked to higher morbidity. Whether circulating extracellular vesicles (EVs) and their RNA cargo directly impact its pathogenesis remains unclear. Methods: We investigated the transcriptional effects of circulating EVs from patients with CRS on renal epithelial/endothelial cells, using a microfluidic kidney chip model (KC). We performed small RNA-seq and regression against serum creatinine to prioritize subsets of EV miRNAs associated with renal function. Long RNA-seq was performed on the same EVs to identify the source organs via deconvolution analysis. In silico pathway analysis, human genetics, and interrogation of expression of miRNA target genes in the KC model and in a separate cohort of individuals post-renal transplant with microarray-based gene expression were performed for validation. To enhance the rigor of our observation, kidney epithelial cells were treated with corresponding anti-miRs and ago-miRs under various experimental conditions. Results: Renal epithelial and endothelial cells in the KC model exhibited uptake of EVs. EVs from patients with CRS led to higher expression of renal injury markers ( IL18 , NGAL , KIM-1 ), a greater cystatin C secretion relative to non-CRS EVs. Small RNA-seq and regression identified 15 miRNAs related to creatinine, targeting 1143 gene targets specifying pathways relevant to renal injury, including TGF-b and AMPK signaling. Deconvolution analysis identified 6 major organs as the main source of the EVs. Finally, we observed directionally consistent changes in expression of TGF-b pathway members (BMP6, FST, TIMP3) in KC model exposed to CRS EVs, as well as in the cells treated with corresponding inhibitors and mimics of miRNAs. Similar trend was observed in renal tissue after transplant rejection. Mendelian randomization suggested a role for FST in renal function. Conclusion: EVs from patients with CRS directly elicit adverse transcriptional and phenotypic responses in a KC model by regulating biologically relevant pathways, suggesting a novel role for EVs in CRS.
Abstract P1005: Parallel Identification Of Gene-Environment Interactions In Cardiac Development Using Human Induced Pluripotent Stem Cells
Authors: Masataka Nishiga, Chun Liu, Lichao Liu, Lei Stanley Qi, Joseph C Wu
Journal: Circulation Research (2023)

Most human diseases are influenced by both genetic factors and environmental factors. However, it is not easy to identify causative combinations of genes and environmental factors that interplay in disease development. Congenital heart defects (CHDs), which is the most common birth defect occurring 1% of newborns in the US, are primarily caused by genetic mutations. On the other hand, phenotypes of CHDs are typically inconsistent among individuals with the same variants and the penetrance is often incomplete, which suggests the important role of environmental factors. Environmental factors known to be involved in the development of CHDs include maternal smoking, diabetes, inflammation, and use of certain medications. Here, we investigated gene-environmental interactions in cardiac development. First, we developed a CRISPR-screen system that screens essential genes in cardiac differentiation from human induced pluripotent stem cells (iPSCs). Our custom CRISPRi library targets ~ 700 genes, which are enriched in human adult or fetal hearts. Our screen system successfully identified positive control genes such as TNNT2, TNNC1, and TBX20 as well as genes that have not been intensively investigated in human cardiac development such as BAMBI and SMAD6. Second, to identify gene-environment interactions, we used the system under the exposure to various environmental stresses such as nicotine, ethanol, inflammatory cytokines, and multiple teratogenic drugs and identified stress-specific gene-environment interactions. This approach is applicable to any other screens of gene-environment interactions.
Abstract P2100: Highly Localized Myocardial Expression Of Brain Natriuretic Peptide In Patients With Mitral Valve Prolapse
Authors: Jes-Niels Boeckel, Stephan Erbe, Ricardo Spampinato, Benjamin Meder, Michael A Borger, Ulrich Laufs, Maja-Theresa Dieterlen, Daniel Lavall
Journal: Circulation Research (2023)

Mitral valve prolapse (MVP) is a common cause of mitral regurgitation (MR), adverse left ventricular (LV) remodeling and arrhythmias. MVP induces mechanical stretch to the inferobasal (INF) myocardium and papillary muscles. The underlying regional and molecular pathology of MVP-induced LV remodeling remains incompletely understood. The aim was to characterize the molecular effects of mechanical stretch by comparing the regional gene expression of the INF region of LV in patients with MVP. Biopsies were obtained from the INF LV and the interventricular septum during mitral valve repair surgery for MVP-induced primary MR. Spatial transcriptome sequencing results correlated with histological staining of fibrosis in the INF and septal regions (R=0.97, P&lt;0.0001). The extent of fibrosis was similar between the INF region and the septal control in the respective patients with MVP. The localized fibrotic areas of the INF region showed decreased expression of cardiac myocyte genes and increased expression of fibrous and EndMT markers. In the INF region, we identified a transition zone between healthy myocardium and fibrous tissue. This transition zone showed increased expression of the NPPB gene encoding brain natriuretic peptide (BNP), whereas NPPB was not increased in the septal region of the same patients, and was confirmed by qPCR (NPPB +6.4-fold, N=11, P=0.004). The INF border zone is characterized by increase expression of NPPB, IGFBP2 and MFGE8, which have been described to be associated with adverse LV remodeling in heart failure. The serum NT-proBNP levels (mean 276.8 ± 121.6 pg/ml) of the patients correlated with NPPB levels from the INF region (R=0.76, P=0.01, N=9), whereas no correlation was found with NPPB levels from the septal control regions (R=0.17, P=0.65) of the same patients. In conclusion, spatial transcriptome analysis in MVP patients identifies a transition zone of the INF region of LV which is exposed to high mechanical stretch. This localized transition zone has a specific gene expression profile, e.g. with increased NBBP expression that correlates with increased NT-ProBNP serum concentrations. Our results indicate that mechanical stretch induces highly localized myocardial pathologies with systemic consequences.
Abstract P3205: Differential Adaptation To Mitochondrial Ca <sup>2+</sup> Overload In The Left And Right Ventricles
Authors: Jae Hwi Sung, Hector Chapoy Villanueva, Kurt W Prins, Julia C Liu
Journal: Circulation Research (2023)

Mitochondrial Ca 2+ (mtCa 2+ ) overload has emerged as a potential contributor to heart failure (HF), possibly through inducing oxidative stress. In HF, right ventricular (RV) function is predictive of mortality, and the RV is more vulnerable to oxidative stress than the left ventricle (LV). Therefore, how the response to mtCa 2+ overload might differ in the RV and LV is critical; however, ventricle-specific mtCa 2+ handling is still poorly understood. We sought to induce cardiac mtCa 2+ overload via genetic manipulation of the mitochondrial calcium uniporter complex (mtCU) formed by the MCU pore and several regulatory subunits. mtCU stoichiometry shapes mtCa 2+ kinetics: loss of mitochondrial calcium uptake 1 (MICU1) induces mtCa 2+ overload, and reduced essential MCU regulator (EMRE) to MCU ratio decreases mtCa 2+ uptake rate. Hypothesizing that mtCa 2+ overload differentially affects LV and RV function, we generated tamoxifen (Tmx)-inducible cardiac-specific Micu1 knockout mice ( Micu1 cKO ) . After confirming that MICU1 loss at 1 week post-Tmx resulted in mtCa 2+ overload in both ventricles, we explored how the LV and RV responses diverge. In Micu1 cKO mice, LV function assessed by echocardiography declined at 4 weeks post-Tmx but recovered partially by 6 weeks. However, impaired RV function at 4 weeks post-Tmx persisted at 6 weeks and longer, without evidence of pulmonary hypertension. Interestingly, at 7-9 weeks post-Tmx, mtCa 2+ levels and oxidative stress remained elevated in the RV but returned to control levels in the LV. Concurrently, EMRE protein levels and mtCa 2+ uptake rate were reduced only in the LV, suggesting that the LV has greater capacity to adapt to mtCa 2+ overload via downregulation of EMRE. We further traced this LV-specific adaptive response to increased maturation of the mAAA-proteases that degrade EMRE. In summary, mtCa 2+ overload induced by MICU1 deletion results in greater oxidative stress and functional impairment over time in the RV than the LV due to absence of compensatory EMRE reduction in the RV.
Abstract P3007: Rosuvastatin-eluting Gold-nanoparticle-loaded Perivascular Wrap For Enhanced Arteriovenous Fistula Maturation In A Murine Model
Authors: Benjamin M Martin, Carleigh L Klusman, Joy Vanessa D Perez, Allan John R Barcena, Marvin R Bernardino, Erin Marie D San Valentin, Jossana A Damasco, Huckie C Del Mundoa, Karem A Court, Biana Godin, Natalie Fowlkes, Richard Bouchard, Jizhong Cheng, Steven Y Huang, Marites P Melancon
Journal: Circulation Research (2023)

Background: Arteriovenous fistulas (AVFs) are a vital form of arteriovenous access for patients requiring hemodialysis, but they are linked to overall morbidity and mortality when they fail to mature. The most common cause of AVF non-maturation is neointimal hyperplasia (NIH). To minimize the effects of NIH, a perivascular wrap composed of polycaprolactone (PCL), rosuvastatin (ROSU), and gold nanoparticles (AuNPs) was created. Objectives: This study assessed the impact of ROSU-eluting, radiopaque resorbable perivascular wraps on pathologic NIH in a chronic kidney disease (CKD) rodent model of AVF. Methods: Electrospun PCL wraps containing AuNPs and/or ROSU were monitored for in vitro AuNP release, ROSU elution, and cell viability. The wraps were implanted around an AVF in a CKD rodent model for in vivo ultrasound (US) and micro-computed tomography (mCT) imaging. AVF specimens were collected for histological analyses. Results: Cell viability was preserved in the presence of both AuNP- and ROSU-containing wraps. In vitro release of ROSU and AuNPs correlated with in vivo findings of decreasing radiopacity on mCT over time. AuNP-loaded wraps had increased radiopacity compared with PCL-alone wraps and control AVFs without wraps. The addition of ROSU decreased US and histologic measurements of NIH. Conclusions: The reduced NIH seen with ROSU-loaded perivascular wraps suggests a synergistic effect between mechanical support and anti-hyperplasia medication. Furthermore, AuNP loading increased wrap radiopacity. Together, our results show that AuNP- and ROSU-loaded PCL wraps induce AVF maturation and suppress NIH while facilitating optimal implanted device visualization.
Abstract P2020: Binding Of Filamin C With Actin Is Essential For Cardiac Development And Function
Authors: Xiaohai Zhou, Xi Fang, Sujay S Ithychanda, Tongbin Wu, Yusu Gu, Li Wang, Julius Bogomolovas, Jun Qin, Ju Chen
Journal: Circulation Research (2023)

Filamin C (FLNC), a filamin family member predominantly expressed in striated muscles, is crucial for bridging the extracellular matrix and the cytoskeleton in cardiomyocytes (CMs), and the maintenance of heart integrity and function. FLNC consists of an N-terminal actin-binding domain (ABD) and 24 immunoglobulin (Ig)-like repeat domains at C-terminus. Many pathogenic mutations on N-terminal ABD have been found in patients with cardiomyopathies. However, little is known about how the actin-binding activity intrinsically contributes to the function of FLNC in mammalian hearts. Using structure-based design, we mutated two key actin binding residues F93 and L98 into Ala and Glu respectively in FLNC ABD (F93A/L98E) and show that the mutations completely disrupted the FLNC-actin interaction. We then generated a knock-in mouse model, demonstrating that loss of FLNC-actin interaction in embryonic CMs led to embryonic lethality and cardiac developmental defects displayed by ventricular rupture and reduced CM proliferation. Moreover, disruption of FLNC-actin interaction in adult CMs resulted in severe DCM phenotypes and reduced survival rate, accompanied with aberrant levels of key cytoskeleton components. These phenotypes resemble those of FLNC knockout mouse models, demonstrating a vital role of the FLNC-actin binding in the function of CMs. Our results also provide a foundation for understanding the mutation-induced cardiomyopathies associated with dysregulation of FLNC ABD-actin interaction.
Abstract P2158: <i>In Vivo</i> Dissection Of A CRISPR/Cas9-Mediated Precise Genome Editing Mechanism
Authors: Sanchita S Dey, Nathan J VanDusen
Journal: Circulation Research (2023)

Genomic sequencing has uncovered many genetic variations that interfere with development and function. Our inability to make precise and permanent genome edits limits our ability to treat genetic disorders. However, CRISPR/Cas9 has been demonstrated to be a potent tool for genome editing, with enormous therapeutic potential. Furthermore, the use of adeno-associated virus (AAV) to deliver CRISPR/Cas9 components, as well as a donor template for homology directed repair (HDR; AAV-HDR), has shown impressive editing efficiencies, particularly in vitro . In comparison, in vivo studies have shown more modest editing efficiencies, with large variation between target loci. Thus, to employ this strategy therapeutically it is imperative to establish a robust understanding of the underlying mechanism, which can then be exploited to improve efficiency. Thus far, the absence of high-throughput tools that enable systematic analysis has hindered efforts to explore and enhance AAV-HDR efficiency. Here we employ two novel high-throughput methodologies for measuring in vivo AAV-HDR editing efficiency in cardiomyocytes of Cas9-expressing mice. In our first approach we analyze the locus-dependent variability of AAV-HDR efficiency, with the goal of identifying the genomic characteristics of high-efficiency loci. In the second approach, we utilize a high-throughput pooled CRISPR KO screen to identify the DNA-repair factors required for efficient gene editing. This approach has uncovered several novel regulators of cardiac AAV-HDR, which we are currently working on characterizing. Collectively these studies will provide insights into the molecular mechanism of AAV-HDR, and we anticipate that these advances will promote development of AAV-HDR based therapies.
Abstract P2110: Fibroblast-specific Smad6 Restrains Adverse Remodeling And Dysfunction Following Myocardial Infarction
Authors: Harikrishnan Venugopal, Izabela Tuleta, Anis Hanna, Akihiko Kubota, Silvia C Hernandez, Claudio Humeres, Fenglan Zhu, Nikolaos G Frangogiannis
Journal: Circulation Research (2023)

Signaling induced by the Transforming Growth Factor (TGF)-β superfamily members in fibroblasts plays a central role in repair and remodeling after myocardial infarction (MI). However, TGF-b signals need to be tightly regulated, as excessive or sustained fibroblast activation after MI can accentuate fibrosis, precipitating heart failure. The inhibitory Smads, Smad6 and Smad7, function as endogenous negative regulators that restrain TGF-β and BMP signaling. We have recently demonstrated that fibroblast-specific Smad7 restrains fibrosis after MI acting through TGF-dependent and -independent pathways. However, the role of Smad6 in tissue repair and fibrosis following injury is not known. We hypothesized that Smad6 expression in infarct fibroblasts may play an important role in repair and remodeling of the heart, regulating TGF-b and BMP-mediated responses. In a mouse model of non-reperfused MI, Smad6 expression was increased in infarct fibroblasts and myofibroblasts at 7d post-infarction. To investigate the role of Smad6 in injury and repair, we used CRISPR/Cas9 to generate Smad6 loxp mice. These animals were bred with Col1a2CreER mice to generate fibroblast-specific conditional Smad6 KOs (FS6KO). 7d after MI, FS6KO mice had accentuated systolic and diastolic dysfunction (p&lt;0.01, N=10) associated with scar expansion, accentuated fibrosis, and higher myofibroblast density in the infarct area and border zone. Fibroblast-specific Smad6 loss increased collagen denaturation in the infarct and border zone. In vitro, siRNA knockdown experiments showed that Smad6 suppresses collagen and fibronectin expression, and modulates protease and matricellular gene synthesis. Reactome analysis of RNA-Seq data suggested effects of Smad6 on pathways involved in assembly and crosslinking of collagen fibrils, collagen biosynthesis and degradation, and VEGF-dependent angiogenesis. Furthermore, Ingenuity Pathway Analysis identified signaling by Integrins, Ephrin receptors and Receptor Tyrosine Kinases as key regulators of the effects of Smad6 loss on the fibroblast transcriptome. In conclusion, fibroblast-specific Smad6 restrains adverse remodeling after MI. Ongoing studies explore the molecular mechanisms for the Smad6 effects.